Submission #1121559

#	Time	Username	Problem	Language	Result	Execution time	Memory
1121559		vjudge1	Ice Hockey World Championship (CEOI15_bobek)	C++17	100 / 100	385 ms	8644 KiB

bobek

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define endl "\n"

using namespace std;
using namespace __gnu_pbds;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
template <typename T, typename key = less_equal<T>>
using ordered_set = tree<T, null_type, key, rb_tree_tag, tree_order_statistics_node_update>;

void solve()
{
    ll n, m;
    cin >> n >> m;
    ll a[n];
    for (ll &i : a) cin >> i;
    ll ans = 0;
    if (n <= 20)
    {
        for (ll msk = 0; msk < (1 << n); msk++)
        {
            ll sum = 0;
            for (ll i = 0; i < n; i++) if (msk >> i & 1) sum += a[i];
            if (sum <= m) ans++;
        }
    }
    else
    {
        vector<ll> v;
        for (ll msk = 0; msk < (1 << (n - 20)); msk++)
        {
            ll sum = 0;
            for (ll i = 20; i < n; i++)
                if (msk >> (i - 20) & 1) sum += a[i];
            v.push_back(sum);
        }
        sort(v.begin(), v.end());
        for (ll msk = 0; msk < (1 << 20); msk++)
        {
            ll sum = 0;
            for (ll i = 0; i < 20; i++) if (msk >> i & 1) sum += a[i];
            ans += upper_bound(v.begin(), v.end(), m - sum) - v.begin();
        }
    }
    cout << ans << endl;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    ll t = 1;
    // precomp();
    // cin >> t;
    for (ll cs = 1; cs <= t; cs++)
        solve();
    // cerr << "\nTime elapsed: " << clock() * 1000.0 / CLOCKS_PER_SEC << " ms\n";
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10